The class of polymers of carbon monoxide and olefin(s) has been known for some time. Brubaker, U.S. Pat. No. 2,495,286, produced such polymers of relatively low carbon monoxide content in the presence of free radical initiators, e.g., peroxy compounds. U.K. Pat. No. 1,081,304 produced similar materials of higher carbon monoxide content in the presence of alkylphosphine complexes of palladium salts as catalyst. Nozaki extended the process to prepare linear alternating polymers in the presence of arylphosphine complexes of palladium moieties and certain inert solvents. See, for example, U.S. Pat. No. 3,964,412.
More recently, the class of linear alternating polymers has become of greater interest in part because of the greater availability of the polymers in quantity. These polymers, often referred to as polyketones or polyketone polymers, have been shown to be of the repeating formula --CO--(Z)-- wherein Z is a moiety of ethylenically unsaturated hydrocarbon polymerized through the ethylenic unsaturation. By way of further example, when the unsaturated hydrocarbon is ethylene, the polyketone polymer will be of the repeating formula --CO--(CH.sub.2 --CH.sub.2)--. The general process for the more recent preparation of such polymers is illustrated by a number of Published European Patent Applications including Nos. 121,965 and 181,014. The process typically involves a catalyst composition formed from a salt of a Group VIII metal selected from palladium, cobalt or nickel, the anion of a strong non-hydrohalogenic acid and a bidentate ligand of phosphorus, arsenic or antimony.
The resulting polyketone polymers are relatively high molecular weight thermoplastics having established utility in the production of shaped articles such as containers for the food and drink industry and internal and external parts for the automotive industry, which articles are produced by conventional techniques such as injection molding or extrusion. For some particular application it has been found to be desirable to have properties for a polymeric composition which are somewhat different from those of the polyketone polymers. It would be of advantage to retain the more desirable properties of the polyketone polymers and yet improve other properties. These advantages are often obtained through the provision of a polymer blend.